Binding Models of Copper(II) Thiosemicarbazone Complexes with Human Serum Albumin: A Speciation Study

Copper(II) complexes of thiosemicarbazones (TSCs) often exhibit anticancer properties, and their pharmacokinetic behavior can be affected by interaction with blood transport proteins. Interaction copper(II) an {N,N,S} donor α-N-pyridyl TSC (Triapine) {O,N,S} 2-hydroxybenzaldehyde (STSC) human serum albumin (HSA) was investigated UV–visible electron paramagnetic resonance spectroscopy at physiological pH. Asp-Ala-His-Lys the monodentate N-methylimidazole were also applied as binding models. Conditional formation constants determined for ternary copper(II)-TSC formed HSA, DAHK, based on spectral changes both charge transfer d-d bands. The neutral displays a similar affinity to complexes. partially negatively charged tetrapeptide binds stronger positively Triapine complex in comparison STSC complex, while opposite trend observed which demonstrates limitations use simple ligands model protein binding. studied are able bind HSA fast process, conditional suggest that strength is only weak-to-moderate.